Determination of absolute structure using Bayesian statistics on Bijvoet differences.
Determination of absolute structure using Bayesian statistics on Bijvoet differences.
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DOI：
10.1107/s0021889807059870
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发表时间：
2008-02-01
影响因子：
6.1
通讯作者：
Spek AL
中科院分区：
文献类型：
--
作者：
Hooft RW;Straver LH;Spek AL
描述了一个最大似然法的生物活性分子的绝对结构测定。介绍了一种新的概率方法，用于确定一个化合物的绝对结构，这是已知的对映体纯的基础上Bijvoet对强度差。新方法提供了不同模型的手性组成的结构的相对概率。这种类型的分析结果也可以转换为新值的形式，沿着相关的标准不确定度，类似于众所周知的Flack x参数的值。我们得到的标准不确定度通常约为Flack x参数值的标准不确定度的一半。建议的形式主义是特别适合的绝对配置确定从衍射数据的生物活性（药物）化合物，其中最强的共振散射信号往往来自氧。结果表明，在这种情况下，根据Cu Kα数据，甚至在某些情况下，根据仔细测量的Mo Kα数据，都可以作出可靠的绝对构型指定。
A description is given of a maximum-likelihood approach to absolute structure determinations of biologically active molecules. A new probabilistic approach is introduced for the determination of the absolute structure of a compound which is known to be enantiopure based on Bijvoet-pair intensity differences. The new method provides relative probabilities for different models of the chiral composition of the structure. The outcome of this type of analysis can also be cast in the form of a new value, along with associated standard uncertainty, that resembles the value of the well known Flack x parameter. The standard uncertainty we obtain is often about half of the standard uncertainty in the value of the Flack x parameter. The proposed formalism is suited in particular to absolute configuration determination from diffraction data of biologically active (pharmaceutical) compounds where the strongest resonant scattering signal often comes from oxygen. It is shown that a reliable absolute configuration assignment in such cases can be made on the basis of Cu Kα data, and in some cases even with carefully measured Mo Kα data.